ELI5: Explain Like I'm 5

Picard variety

Okay kiddo, have you ever played with different shapes and colors of building blocks? Well, imagine that we have a really fancy set of blocks called "algebraic varieties," which are made up of a bunch of points in space that satisfy certain equations. One type of algebraic variety is called a "Picard variety."

Imagine we have a big piece of paper, and we're going to draw some dots on it. We can connect the dots with lines or curves, and this creates a shape. In algebraic geometry, we can do something similar: we take a set of equations, find all the points that satisfy those equations, and connect them in a certain way. This gives us an algebraic variety.

A Picard variety is a particular type of algebraic variety that has something called a "Picard group." This group is like a secret code that tells us how the variety is put together. It's kind of like the number of different ways we can connect the dots on our paper to make a shape. The Picard group measures how "twisty" or "bendy" our variety is.

Now, why do we care about Picard varieties? Well, they're really important in studying certain types of equations, and they have connections to other areas of math like algebraic topology and number theory. But for now, just remember that a Picard variety is a special kind of shape that we can make using algebraic equations, and it has a secret code called the Picard group that tells us how the shape is put together.